Friday, February 4, 2011

The fidaxomicine, promising new antibiotic against Clostridium difficile

Clostridium difficile is a bacterium certainly less known than Staphylococcus aureus or Escherichia coli, but which nevertheless cause intestinal infections and daunting and increasingly difficult to overcome. However, a new antibiotic, fidaxomicine, appears as effective as those currently used, and could especially help to reduce nearly 50% of recurrences unfortunately frequent. Infection becoming more common in hospitals Clostridium difficile survives in nature as spores, found particularly in soil and hospitals. This bacterium is also part of the normal intestinal flora of humans. This is one of the leading causes of nosocomial infections (occurring in medical settings) in Western countries and is increasing in recent years, which worries the medical profession and health authorities. The infection usually occurs on antibiotics, prescribed for another reason: these antibiotics will disrupt intestinal flora and Clostridium difficile will then multiply, releasing a toxin that will cause an intestinal infection. Clinically, this translates into a sort of gastro-enteritis intense profuse watery diarrhea, fever and abdominal pain. Main feature of this infection? The formation of membranes, or pseudomembrane, which line the intestines (visualization by colonoscopy), hence the name given to this infection: pseudomembranous colitis (also possible with other bacteria, but more rarely). Possible serious complications Infection may be complicated by septic shock or excessive dilatation of the colon (toxic megacolon, a surgical emergency), which can result in a number of cases to death. Certainly, two antibiotics are still effective, metronidazole, vancomycin-and manage to roll back the infection, but unfortunately resistance appear. Moreover, their use in exhibits at least one quarter of cases of recurrence, just as dangerous. Consequently, many teams working on the development of a new more effective treatment or a vaccine. A promising new antibiotic According to the results of a study published today in the New England Journal of Medicine, a new antibiotic, Fidaxomicine (macrocyclic antibiotic produced by the U.S. laboratory Optimer Pharmaceuticals) decreases by 45% the rate of recurrent infection Clostridum difficult. To achieve this, Thomas J. Louie and his team administered the drug or vancomycin at 548 patients with reported infection (detection of bacterial toxin). On healing of the infection, the results were comparable, with 88.2% of patients cured with fidaxomicine and 85.8% with vancomycin. Cons by the recurrence rate was therefore significantly lower in group fidaxomicine (15.4% vs. 25.3%, down from 45% risk). Moreover, this drug did not cause more side effects. Its mode of action it would save the intestinal flora, thereby reducing the risk of recurrent infection. The future use of this antibiotic could help stem the current proliferation of cases of Clostridium difficile infections, which represent a new breakthrough in the fight against nosocomial infections. Jean-Philippe Riviere Source: "Fidaxomicin versus Vancomycin for Clostridium difficile Infection", Thomas J. Louie et al. New England Journal of Medicine, February 3, 2011, summary of the study available online